2010 Easter Lilies
Wednesday, 25 November 2009 13:47
Rich McAvoy, University of Connecticut provided a good article on scheduling the 2010 Easter Lily crop. For the 2010 Easter Lily schedule, comments and pictures see: 2010 Easter Lilies
Easter falls on a mid-date in 2010 (April 4). This is on the early end of the mid-date calendar but allows enough time for proper programming and forcing. According to the schedule forcing will begin on December 6th.
Many Easter lily problems such as uneven and delayed flowering and reduced flower number can be traced to improper precooling. To avoid these problems, the lily bulb must be exposed before forcing to 1,000 hours (6 weeks) of cool temperature (42°F). This treatment is called vernalization.
If you know or suspect that bulbs have not received the entire six weeks of cooling by the time greenhouse forcing is scheduled to begin, then provide insurance lighting. Insurance lighting refers to night break lighting used to produce a long day photoperiod. When insurance lighting is used immediately following shoot emergence, it will produce the same effect as bulb cooling or vernalization. Therefore, insurance lighting can be used to substitute for inadequate bulb cooling. Provide one day of insurance lighting for each day of lost cooling. Incandescent, fluorescent, or HID lighting in excess of 10 foot candles from 10 pm to 2 am daily will provide the necessary night break. Overcooling will cause plants to have fewer leaves and flowers, have short lower leaves and will flower quicker, so stick to your schedule.
Fertilize when lilies emerge and continue to within 7 days of sale. Many growers alternate between 15-0-15 and 20-10-20 using a range from 200-400 ppm. The medium electrical conductivity (EC) should not be allowed to exceed 3-3.5 mmho/cm based on a saturated media extract. Provide a clear watering before lilies are shipped to reduce salt levels in the potting medium and maximize lily-keeping quality. Do not withhold water or fertilizer to slow development. Avoid overwatering to prevent root rot problems.
Easter lilies are very susceptible to root rot, which becomes most evident later in the crop cycle. Monitor roots, avoid overwatering and use fungicides for both Pythium and Rhizoctonia. Note there is significant Subdue resistance to Pythium evident in greenhouses this past year according to the UMass Plant Diagnostic laboratory.
More information: The 2010 Gloeckner Easter Lily Production Guide (28 pages)
Tina Smith, UMass
